Brief Answer:
Post inflammatory pigmentation ,Mucoid plaque

Detailed Answer:
Hello Musegreat...
Welcome to Ask a doctor.
I am Dr Ajeet XXXXXXX

Post inflammatory pigmentation is an increase in melanin which is triggered by the way skin is healing after inflammation or injury or trauma.The local inflammatory resoponse cause the melanocytes to produce more of melanin pigment in the skin thus causing pigmentation.
Melanocytes are pigment cells and melanin is the pigment that defines the color of a person's skin.Melanin is more in black and is less in white skinned people.
As far as treatmrnt is concerned,you can not do much about it.Most of times it is irreversible.Avoid exposure to direct sunlight.To fade it, you can use steroid creams like Desonide which is a mild corticosteroid.Over use is bad.
Fortunately,it is on your back,so there are no cosmetic concerns.

Mucus is normally secreted by our gut but in small amounts which is invisible to naked eye.
Most common cause of excess mucus in stools is bacterial infections (caused by bacteria such as Campylobacter, Salmonella,Shigella and Yersinia).These bacteria often cause symptoms like diarrhea,cramping and nausea.I give a two week long course of antibiotics to such patient,specific for abdominal infection.
Irritable bowel syndrome (IBS) is the second common cause of increased mucus production.This symptom is more common in people with diarrhea-predominant IBS than those with constipation-predominant IBS.
IBS is a spectrum of disease which includes ulcerative colitis and chron's disease.
Ulcerative colitis can result in the mucous membrane of the large intestine becoming inflammed and developing ulcers.These ulcers produce excess amount of pus and mucus and can bleed sometimes.
Such patients are treated by anti inflammatory drugs like sulfasalizine and prednisolone,pain relivers like acetaminophen,immunosuppresants like azathioprine and ashort course antibiotics.At this juncture,I want to know that whether your colonoscopy has been done?

You should take small frequent meals instead of large three.Keep yourself well hydrated.Take rich fiber diet.Be physically active.Have raw veggies and fruits.Avoid milk and milk products if you are not able to digest.You can take isabghula husk and commercially available laxatives like lactulose s.o.s.
Avoid tea,coffee,alcohol,spicy,fatty and junk food.Have soft diet which is easy to digest.Avoid gassy foods.
Don't be chronically constipated because this causes foecal impaction and to make the things worse,spurious diarrhea.
You can have Proctosedyl enema if the situations worsens and if need arises.That would be free from side effects but should not be abused.

When you had gone through water and clear vegetable fasting diet,your system got detoxified and it was back to normal.Continue having high fiber diet and do more and more life style and dietary changes and you will improve.
Hope that I have answered your query and if you have any doubts,please let me know.
Stay healthy and stay blessed.
Regards

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Brief Answer:
Post inflammatory pigmentation ,Mucoid plaque

Detailed Answer:
Hello.
Unfortunately you can't do much as far as melanin production is concerned.Avoid exposure to direct sunlight.Use steroid creams like Desonide which is a mild steroid and would fade it.Avoid going in sun.
Eat most of red, orange and yellow vegetables which contains, beta carotene, which is a blocking agent of melanin.Scrub you skin daily.Pigmentation can be reduced gradually by scrubbing also.
The fastest way to permanently reduce melanin in skin is by undergoing a laser treatment,but this option is costly.
Of course stop worrying.It does no good.Stress leads to release of some hormones in the body which affects all body functions.Meditate,if you can.
Make dietary and life style changes as I have advised.
If the symptoms do not improve,please consult a gastroenterologist who will do endoscopic examination(colonoscopy). It is an outdoor procedure,which does not require hospitalization and anesthesia.He might take biopsy as well and would start the treatment accordingly.

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